Hi, Anyone know what digital mode is being used on the 17 Meter band between 18.103 and 18.104 Mhz, around 23 Zulu Time? It Sounds like MFSK and a few others but I've never been able to decode it with fldigi. The sound is like several notes, played slowly over time.

DominoEX and Thob sound fantastic - they deserve more air time because of their musical qualities alone.Would it be in breach of one' s license to send meaningful messages that just happened to sound like nice tunes

Sounds like JT-65HF, based on the frequency. JT-65HF has a 48-second transmission window, 12 seconds of decode time (and a few seconds of forgiveness in computer clock accuracy), and then the other station starts.

18102.0 USB is the JT65 frequency. That's almost certainly what you heard. To me it sounds like someone playing a depressed electric keyboard with one finger.

It's an odd, yet strangely appealing mode. Because it is works so well with almost no power, you can make contacts at very long distances even in very poor conditions. The primary drawback is that it takes 7 minutes to make a very basic QSO exchange of grid square and signal report.

You could then call CQ again on the 7th minute, making the QSO 6 minutes.

Maybe I'm missing something, but I don't see how it's possible to have a 4 or 5 minute QSO unless you're not exchanging signal reports (I think this is typical for EME) or you're not confirming receipt of the signal report. If you call CQ again without responding to the signal report, I'd think many people would assume that you did not receive the report and they won't log the QSO.

Just timed a JT65 QSO with all the exchanges trasnmittedFirst call from the station calling me was at 14:31:33I sent his reportHe sent my reportI sent RRRHe sent 73I sent 73QSO ended at 14:36:45

Maybe it is the Canadian atmosphere that makes it faster

Either way it is a good mode to work DX, or North America and do so with low power. Guys should try turning the output down to under 5 watts and see what happens. I just finished working Mexico and FL with 4 watts to a dipole that has an apex of 28 feet. So hardly a big gun antenna. I have worked VK's on 40 M early in the morning with 10-15 watts to a dipole. Amazing mode. But yes, not for everyone.

I have made some incredible QSO's with low power and dipoles. I sometimes use the miles per watt rating (although a better measure would consider the antenna gain and effective radiated power, because 5 watts and a yagi is going to get a LOT better response in most cases than 5 watts and a single wire). Anyway, 1000 miles per watt is my typical benchmark, and I have done this many times....working into Europe, Asia, Oceana with just 5 watts.

And just last night, I did my first Earth-Moon-Earth QSO's using JT65. Granted I was using 350 watts and a 9 element yagi on 144 MHz, but the round trip distance was about 750,000 miles. So that still comes out to more than 2000 miles per watt.

Just timed a JT65 QSO with all the exchanges trasnmittedFirst call from the station calling me was at 14:31:33I sent his reportHe sent my reportI sent RRRHe sent 73I sent 73QSO ended at 14:36:45

From your posted times, it appears your clock wasn't sync'ed properly, if your times include start at 33 seconds and end at 45 seconds???

From the JT65-HF spec, if clocks are properly sync'ed, TX will start at xx:xx:01 and end at xx:xx:48 with decode time from xx:xx:49 to xx:xx:59 and then 1 second of delay and starts again with other station.

Just timed a JT65 QSO with all the exchanges trasnmittedFirst call from the station calling me was at 14:31:33I sent his reportHe sent my reportI sent RRRHe sent 73I sent 73QSO ended at 14:36:45

From your posted times, it appears your clock wasn't sync'ed properly, if your times include start at 33 seconds and end at 45 seconds???

From the JT65-HF spec, if clocks are properly sync'ed, TX will start at xx:xx:01 and end at xx:xx:48 with decode time from xx:xx:49 to xx:xx:59 and then 1 second of delay and starts again with other station.

Gene W5DQ

My logbook clock is synced with my JT65 clock, which is synced to a national time server from your country.

I must be doing something right with JT65, I have well over 1100 contacts on that mode with casual operating over the past 1 1/2 years.

Plus I don't really pay any attention to the time it takes to start and finish a QSO, I just work em and log em!

Just timed a JT65 QSO with all the exchanges trasnmittedFirst call from the station calling me was at 14:31:33I sent his reportHe sent my reportI sent RRRHe sent 73I sent 73QSO ended at 14:36:45

From your posted times, it appears your clock wasn't sync'ed properly, if your times include start at 33 seconds and end at 45 seconds???

From the JT65-HF spec, if clocks are properly sync'ed, TX will start at xx:xx:01 and end at xx:xx:48 with decode time from xx:xx:49 to xx:xx:59 and then 1 second of delay and starts again with other station.

Gene W5DQ

My logbook clock is synced with my JT65 clock, which is synced to a national time server from your country.

I must be doing something right with JT65, I have well over 1100 contacts on that mode with casual operating over the past 1 1/2 years.

Plus I don't really pay any attention to the time it takes to start and finish a QSO, I just work em and log em!

I too have many JT65-HF QSOs, but probably not 1100+ like you. But doing something 1100+ times wrong doesn't make it right, does it??? I also see folks running in what is basically referred to as 'all knobs right'. Their waterfall trace looks like someone used a 3" paintbrush to make it. Usually the s/w will NOT decode them properly unless you roll back the RF Gain and do some DSP filtering on them and then it might work.

I'm not saying that the time is super critical and being off a few seconds doesn't work. I have see signals on the waterfall starting several seconds early to ending several seconds late and the software seems to decode them ok (caveat : sometimes). I simply stated that if you read the specification, the cycle SHOULD start at xx:xx:00 followed by 1 second delay and then 47 seconds of tones (1 to 48 seconds) followed by 11 seconds of decode period for a 60 second cycle window. Then it repeats.

I know that my JT65-HF clock starts EXACTLY at xx:xx:00 with PTT ON and at xx:xx:48 PTT goes off. I am also synced to the Boulder, CO Time source (I don't recall offhand exactly which server I am pointed at). I use TIMESYNC utility and have a 5 minute resync window.

But if you're making contacts then keep after it. Since it seems being accurate on the timing isn't too important to you, I truly hope your not one of the signals made with the 3" paintbrush?

I too enjoy JT65-HF, but I use it when nothing else is on I want to try to work or when I have alot of time to waste. Much prefer RTTY or CW.

No my signal is not the 3 inch wide paint brush on JT65. No ALC showing at all, no power out put above 20 watts (and that is rarely used except to work some DX) Most of the time I run 10 watts or less. You won't see me signing with 50W YAGI 73

I have seen the signals you talk about, but that is not how mine look.

Yes at times the timing might be off a little bit. The time could be like that because I do not always get right to the answering of someone who has called CQ.

But as I said something must be working or it would be hard to log as many QSO's with that mode as I have.

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